Browsing by Author "Silva, J."
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- Effects of LED lighting on Nannochloropsis oceanica grown in outdoor raceway pondsPublication . Carneiro, M.; Maia, Inês Beatriz; Cunha, P.; Guerra, I.; Magina, T.; Santos, Tamara; Schulze, Peter S.C.; Pereira, H.; Malcata, F. X.; Navalho, J.; Silva, J.; Otero, A.; Varela, JoãoGrowth in most microalgal mass cultivation systems is light-limited, particularly in raceway ponds (RWP) where the light path is higher. Artificial lighting can be a promising solution to diminishing dark zones and enhance microalgal productivity. Therefore, our goal was to prevent the cell shift from photosynthesis to a respiration-only stage by resorting to LED illumination. Nannochloropsis oceanica cultures were accordingly grown out-doors in a preliminary small-scaleexperiment, followed by pilot-scale trials. In the former, three 3.0-m(2) RWP were set up under three distinct conditions: 1) without LEDs (control); 2) LEDs turned on during the night; and 3) LEDs turned on for 24 h. In the pilot-scale trial, one of two 28.9-m(2) pilot-scale RWPs was coupled to the best LED setup - determined in the small-scale preliminary experiment - using the same light intensity (normal mode) and half of the intensity (economy mode), with the second RWP serving as a control. In the preliminary experiment, the use of LEDs for 24 h was deemed as not helpful during daytime, before the culture reached asymptotic to 0.5 g DW L-1 - when dark zones appeared during the day due to sunlight attenuation in the 0.1 m-deep cultures. Overall, use of LEDs increased biomass growth chiefly by increasing nighttime productivities - materialized in higher chlorophyll, protein, and carbohydrate productivities in LED-lit cultures. A higher impact of LED lighting was observed under lower sunlight irradiances. A preliminary economic analysis indicates that use of LEDs in RWPs outdoors should be considered for high-value metabolites only.
- Gla Rich Protein (GRP) is associated to osteoarthritis being highly accumulated in the joint tissues and synovial fluidPublication . Cavaco, S. I.; S B Viegas, Carla; Marta, R.; Acacio, R.; Silva, J.; Morera, J. L.; Teixeira, A.; Smit, E.; Herfs, M.; Vermeer, C.; Simes, D
- Heterotrophy as a tool to overcome the long and costly autotrophic scale-up process for large scale production of microalgaePublication . Barros, A.; Pereira, H.; Campos, J.; Marques, A.; Varela, J.; Silva, J.Industrial scale-up of microalgal cultures is often a protracted step prone to culture collapse and the occurrence of unwanted contaminants. To solve this problem, a two-stage scale-up process was developed - heterotrophically Chlorella vulgaris cells grown in fermenters (1st stage) were used to directly inoculate an outdoor industrial autotrophic microalgal production unit (2nd stage). A preliminary pilot-scale trial revealed that C. vulgaris cells grown heterotrophically adapted readily to outdoor autotrophic growth conditions (1-m3 photobioreactors) without any measurable difference as compared to conventional autotrophic inocula. Biomass concentration of 174.5 g L-1, the highest value ever reported for this microalga, was achieved in a 5-L fermenter during scale-up using the heterotrophic route. Inocula grown in 0.2- and 5-m3 industrial fermenters with mean productivity of 27.54 ± 5.07 and 31.86 ± 2.87 g L-1 d-1, respectively, were later used to seed several outdoor 100-m3 tubular photobioreactors. Overall, all photobioreactor cultures seeded from the heterotrophic route reached standard protein and chlorophyll contents of 52.18 ± 1.30% of DW and 23.98 ± 1.57 mg g-1 DW, respectively. In addition to providing reproducible, high-quality inocula, this two-stage approach led to a 5-fold and 12-fold decrease in scale-up time and occupancy area used for industrial scale-up, respectively.
- Portuguese recommendations for the management of Raynaud’s phenomenon and digital ulcers in systemic sclerosis and other connective tissue diseasesPublication . Santiago, T.; Duarte, A. C.; Sepriano, A.; Castro, A.; Rosa, B.; Resende, C.; Oliveira, D.; Dourado, D.; Costa, E.; Santos, F. Cunha; Terroso, G.; Boleto, G.; Silva, I.; Barbosa, L.; Silva, J.; Neves, J. Sousa; Salvador, M. J.; Gonçalves, M. J.; Guerra, M. Gomes; Ferreira, R. M.; Fernandes, R. Duarte; Barreira, S.; Teixeira, C. Silvestre; Tomás, A. L.; Romão, V. C.; Cordeiro, A.Objective: To develop evidence-based recommendations for the non-pharmacological and pharmacological management of Raynaud's phenomenon (RP) and digital ulcers (DUs) in patients with systemic sclerosis and other immune-mediated connective tissue diseases (CTDs). Methods: A task force comprising 21 rheumatologists, 2 surgeons (vascular and plastic), 2 nurses, and 1 patient representative was established. Following a systematic literature review performed to inform the recommendations, statements were formulated and discussed during two meetings (one online and one in-person). Levels of evidence, grades of recommendation (GoR), and level of agreement (LoA) were determined. Results: Five overarching principles and 13 recommendations were developed. GoR ranged from A to D. The mean +/- standard difference (SD) LoA with the overarching principles and recommendations ranged from 7.8 +/- 2.1 to 9.8 +/- 0.4. Briefly, the management of RP and DUs in patients with CTDs should be coordinated by a multidisciplinary team and based on shared decisions with patients. Nifedipine should be used as first-line therapy for RP and/ or DUs. Sildenafil, tadalafil, and/or iloprost IV are second-line options for severe and/or refractory patients with RP and/or DUs. Sildenafil, tadalafil and/or Iloprost IV, should be prescribed for healing and prevention (also including bosentan) of DUs. In patients with RP and/or DUs, non-pharmacological interventions might be considered as add-ons, but there is limited quality and quantity of scientific evidence supporting their use. Conclusions: These recommendations will inform rheumatologists, specialist nurses, other healthcare professionals, and patients about a comprehensive and personalized management of RP and DUs. A research agenda was developed to address unmet needs, particularly for non-pharmacologic interventions.
- Tank and field experiments of short-range acoustic propagation through a seagrass canopyPublication . Felisberto, Paulo; Silva, J. P.; Jesus, Sergio; A.J. Silva; Silva, A.T.; Silva, J.; Santos, R.; Ferreira, H.; Pousao, P.Aiming at monitoring the bubbles released during seagrass photosynthesis in different conditions, three experiments were made: two in an outdoor tank and one in the field. The outdoor tank experiments were conducted in winter and summer conditions with Cymodocea nodosa plants transplanted from a nearby meadow. The field experiment took place in September 2018 on a Posidonia oceanica meadow, where bubbles formation due to plants photosynthesis has been reported. In all the experiments continuous wave pulses in the band 1020 kHz were used to estimate the diel change of effective sound speed and the attenuation over the plants. Additionally, high frequency backscatter images at 0.5, 1, 2 and 4 Mhz were obtained to figure out bubbles signature. The results suggest that even in winter, the tank conditions, without water movement, allows for the formation of a small amount bubbles of small radii. In summer tank conditions, the bubbles formation due to photosynthesis of seagrasses significantly increases, but also algae may contribute for the bubbles formation in the environment. The field experiment was carried out after the peak of a bad weather event. There was no evidence of bubbles formation, what can be related to water movement and leaves stirring, that prevents bubbles formation.